Charles thelismar snedekor



(No Model.)

0. T. SNEDE'KO R. ELECTRIC ARC LAMP.

Patented Sept. 12, 1893.

Witnesses B prrorr e UNITED STATES PATENT OFFICE.

CHARLES THELISMAR SNEDEKOR, OF WORCESTER, MASSACHUSETTS, AS SIGNOR TO THE WVASI-IBURN 8t MOEN MANUFACTURING COMPANY, OF

SAME PLACE.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 504,760, dated September 12, 1893.

Application filed March 20, 1893' Serial No. 466,782. (No model.)

To all whom it may concern.-

Be it known that 1, CHARLES THELISMAR SNEDEKOR, a citizen of the United States, residing at WVorcester, in the county of Worcester and Commonwealth of Massachusetts, have invented certain new and useful Improvements in Arc-Light Holders, of which the following is a specification.

The object of my invention is to provide a 10 holder for are lamps, with the arms so constructed that the insulated wire connecting with the lower carbon may be protected from the heat generated in the lamp. Heretofore in lamps of this class it has been the custom to cast the arms with a recess in which the insulated wire may lie, being secured to the arm by wires. The consequence has been that the insulation would frequently become charred by exposure to the heat generated in the lamp, and would have to be frequently renewed, at considerable expense and inconvenience. To obviate this the connecting wire has sometimes been brought down outside the globe of thelamp,which is objectionz 5 able, because of the shadows thus produced. My improvement is designed to obviate all these difiiculties.

In the drawings, Figure 1 is a front view of my improved holder, showing the peculiar 0 construction of the arms, the covering strip 3 in arm lbeing broken away so as to show the insulated wire 4. Fig. 2 is a vertical, sectional View of arm 1 showing the insulated wire 4. Fig. 3 is a vertical, sectional view similar to 5 Fig. 2, showing the insulated wire 4: packed in non-inflammable substance.

As my invention relates solely to the con-' flat strip bent at its lower end, and held in place by the screw 9 shown at the lower end of arm 2, Fig. 1.

In practice the covering strip being removed the insulated wire is brought through a hole in the top of the casting through the hollow arm 1, and is bent at the lower point 5 where the connections with the lamp are made in the ordinary way; the covering strip is then slipped under the lugs 8, 8, and prevented from dropping down by the screw 9, shown at the bottom of arm 2, Fig.1. In arm 1, Fig. 1, the covering strip is shown for a short distance at the upper end, and is then broken away showing the insulated wire exposed to view the rest of the way.

I may sometimes line the hollow arm with some refractory material, as shown at 6, Fig. 3, which will still further protect the insulation from the heat of the lamp, or I might run a naked wire through the hollow arm, depending for insulation upon the packing placed around the wire, which the construction of my improved arm enables me to use and to hold in place. It will be noticed that both arms are constructed in the same way, arm 1 showing the covering strip broken away for part of the distance, while in arm 2 the covering strip is shown secured in place.

I do not confine myself to hollow arms, square in cross-section, or of any particular shape, nor to arms provided with lugs to hold the covering strip in place; the sides of the arms might be grooved to receive the covering strip, or the strip could be held in place by clamps surrounding the arm, nor do I confine myself to straight arms, for my improvement can be used equally well when the arms are curved.

It willbe seen that my improvement onables me to bring the arms of the lamp down within the globe, and at the same time pro tect the insulation from the heat of the lamp towhich it would otherwise be exposed.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1 In the frame of an arc lamp, an arm with a hollow space sufliciently large to contain an insulated wire, said space being filled with a packing of some refractory material, and covered by a strip of metal secured to the arm.

2. In the frame of an arc lamp, two arms falling within the globe of the lamp, one or both of the arms being hollow, and provided with lugs beneath which a covering strip is confined, whereby the insulated wire Within the space is protected from the heat of the 10 lamp.

3. In the frame of an arc lamp, an arm with a hollow space containing a naked Wire packed in insulating material, said insulating material being held in place by a strip of metal secured to the arm.

CHARLES THELISMAR SNEDEKOR.

Witnesses:

O. G. WASHBURN, R. M. WASHBURN. 

